I have done 2 S4 TII in to S4 N/A swaps now and know every thing that is envolved. I am now looking to put a full S4 TII drivetrain into a clean S5 N/A but have some questions.

What problems will I come up against?

cant I just use the S4 TII engine wire harness and ECU? or

do I have to go Standalone?

Basicly any info will help me, I have a beautiful S5 NA and a full S4 TII drivetrain with a rebuilt motor and hybrid turbo....................I want to put them together! lol

 

Drivetrains don't matter between series, so no problems there. The engine wil physically bolt in, but the wiring and such ar all different between series. IT's not a good idea to try and swap electronics across series. You should find s5 t2 electronics to make teh swap smooth, otherwise you'll have to cut and splice some stuff, which is no fun.

 

even if I use the S4 ECU and wiring harness? because the engine harness connects to the MAF, TPS, injectors ect.

Oh also this motor has no emissions equipment on it, its all been blocked off.

 

The harness inside the car (under the dash) is different.

 

You dont understand. The ecu plugs into the car harness AND the engine harness. Or did you think the engine supplied the ecu with power, crank angle sensor input, coil output, etc.? The plug in the car will not plug into the other series ecu, even if the engine harness of the new engine will.